Sandal upper



FIG. 1 is a perspective view of a sandal upper, showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a front elevation view thereof; and,

FIG. 6 is a rear elevation view thereof.

The sandal sole shown in broken lines is for environmental purposes and do not form a part of the claimed design. 

The ornamental design for a sandal upper, as shown and described. 